Development of a Fluorophore with Enhanced Unorthodox Chalcogen Bonding for Highly Sensitive Detection of Trimethyl Arsine Vapor.

In this work, we report the design of novel fluorophores that bear three benzothiadiazole and benzoselenadiazole groups, respectively, for sensitive detection of trimethyl arsine vapor. In particular, the fluorophore with the benzoselenadiazole groups can form stronger chalcogen bonding with trimethyl arsine than the fluorophore with the benzothiadiazole groups, which in turn triggers much faster and more sensitive fluorescence responses. On the basis of this novel mechanism, fluorescence detection of trimethyl arsine vapor with rapid response (∼3 s), high sensitivity (the theoretical LOD is 0.44 ppb), and high selectivity is achieved on bundled nanofibers from the fluorophore with the benzoselenadiazole groups. Here, the new fluorescence sensor may find wide applications in health and environmental monitoring, arsenic distribution recognition in soil, and arsenic mines exploration.

Transforming Nanofibers into Woven Nanotextiles for Vascular Application.

This study investigates the unique properties, fabrication technique, and vascular applications of woven nanotextiles made from low-strength nanoyarns, which are bundles of thousands of nanofibers. An innovative robotic system was developed to meticulously interweave nanoyarns in longitudinal and transverse directions, resulting in a flexible, but strong woven product. This is the only technique for producing seamless nanotextiles in tubular form from nanofibers. The porosity and the mechanical properties of nanotextiles could be substantially tuned by altering the number of nanoyarns per unit area. Investigations of the physical and biological properties of the woven nanotextile revealed remarkable and fundamental differences from its nonwoven nanofibrous form and conventional textiles. This enhancement in the material property was attributed to the multitude of hierarchically arranged nanofibers in the woven nanotextiles. This patterned woven nanotextile architecture leads to a superhydrophilic behavior in an otherwise hydrophobic material, which in turn contributed to enhanced protein adsorption and consequent cell attachment and spreading. Short-term in vivo testing was performed, which proved that the nanotextile conduit was robust, suturable, kink proof, and nonthrombogenic and could act as an efficient embolizer when deployed into an artery.